Timofei Konstantinovich Tszyu (Russian: Тимофей Константинович Цзю, [tʲɪmɐˈfɛj kɐnstɐnˈtʲinəvit͡ɕ ˈdzːʲʉ] born 2 November 1994) is an Australian professional boxer who held the World Boxing Organization (WBO) junior-middleweight title from 2023 to 2024.

[6] As a soccer player, he was selected to play for multiple local representative teams[7] but his interest in the sport began to wane at the age of 13 when he temporarily relocated to Moscow with his family for a few months before returning to Sydney.

[11] After being away from the sport for four years due to a hand injury,[12] Tszyu made his professional debut in December 2016 when he defeated Zorran Cassidy by unanimous decision (UD) at the Sydney Cricket Ground.

[15] On 26 August 2020, Tszyu defeated former WBO welterweight champion Jeff Horn via eighth-round corner stoppage at the Queensland Country Bank Stadium.

[20] On 22 January 2023 it was announced Tszyu would take on former WBC 154-lb champion Tony Harrison for the WBO interim junior middleweight title on 12 March in Australia.

[22][23] He was elevated to a full champion once Jermell Charlo faced Canelo Alvarez inside the ring for his undisputed super middleweight title on September 30, 2023.

[31][32] On May 30, 2024 it was announced that the fight was canceled on medical advice, with Tszyu requiring more time to heal from the injury sustained in his previous bout against Fundora.